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The Tale of Nidorino
Though Nidorino debuted in Nidorina's secret, he was not a very prominent character compared to Nidorina, and played a backseat role to her, seeing as Nidorina's road to personal change was far more compelling. Additionally, the importance of Eevee to the series and Nidorina being his makeshift mother and consistent caretaker gave them both far more screen time than Nidorino.
The early life of Nidorino is unknown, but what can be gathered from his early appearances is that he is well liked among the inhabitants of the Poke Forest, is known to be attractive, and has presumably lived in the wild all his life. However, it is also known that he has a higher level of education than Nidorina, and perhaps like Nidorina did during her years as a homeless youth, attended a freely open public school while simultaneously living off the land.
Nidorino was one of the few Pokemon Nidorina did not bully, as she was always attracted to him, but too self conscious and full of self defeating thoughts to approach him. Nidorino mutually found Nidorina attractive from the beginning, but kept his distance as to not get thrashed.
Once Nidorina decided to start her life again to make herself whole, Nidorino and Nidorina finally started dating, though when this specifically began is never shown. Nidorino wanted to take his time to get to know Nidorina, but Nidorina, having been broken for most of her life, immediately jumped to the conclusion that Nidorino is the greatest man in all of existence, and fell so deeply in love with him that she'd never be able to climb out of the "bottomless pit of love" in her heart. This made Nidorina sort of clingy, which made Nidorino nervous, but nothing was as bad as the moment Nidoran (♂) and Nidoran (♀) announced their wedding. As soon as Nidorina caught wind of this, she immediately fantasized about being married, too, and then, after being met with some hesitation after asking Nidorino the first time, Nidorina threatened Nidorino to marry her or she'd mutilate him. Nidorina was still recovering from a lifetime of feeling like everyone was against her, so this lashing out was merely habitual and non intended, but Nidorino was too afraid to do anything other than comply, much to Nidorina's elation, and they were wed on the same day as the Nidoran's wedding. Nidorino spent the entire wedding day in shock of how fast this was all happening to him, but it wouldn't be until afterward when a sense of resentment would kick in.
Before Eevee arrived, Nidorino was distant with Nidorina, showing her little affection, and in the process, really hurting her feelings and making her wonder if Nidorino loved her. It was made worse by the fact that she couldn't feel anything but love towards Nidorino, and when all the other couples would reciprocate any romantic feelings while Nidorino phoned it in, she would only, and would always, blame herself, as Nidorina still had low self esteem. Nidorino remained distant and indifferent for a while longer, but the arrival of children such as Charmander and Eevee would awaken maternal instincts in Nidorina, and give her someone she could pour her love onto, as well as practice showing her new and steadily rising sense of compassion for. Of course, Nidorino wasn't happy with Nidorina's adoption of Eevee without first talking it over, and he reluctantly began to look for work in order to provide for a family he still wasn't ready to have.
Over the course of several episodes, however, in seeing the closeness between Eevee and Nidorina, and seeing how much her life had improved since Eevee came into theirs, Nidorino began to soften, finding some joy in having a child, and knowing what a capable mother Nidorina could be. She seemed a lot more radiant when her love was being reciprocated, even through a child, and additionally seeing the lengths Nidorina would go through just to protect Eevee from any threats made him realize that Nidorina really was the right Pokemon to have as a mate. Nidorino, realizing his mistake in being so distant, made a grand gesture by apologizing to Nidorina in public, and then asking Nidorina to remarry him, and this time out of mutual love as opposed to an impatient desire to live a fairytale life. Shortly after, he would finally give Nidorina the gift she had been begging him about for the longest time: a baby. Once Needles was born, Nidorino and Nidorina became much closer than they've ever been in Poke Tales, and things seemed to be looking up from here on out.
The Legend of Nidorino
Nidorino's role became more prominent in Poke Legends, as the focus shifted off of Nidorina primarily, and more on the entire family, specifically both spouses. Eevee had already left for home at the end of Poke Tales, but Totodile would make his appearance very early in the series. Having been down this road before, Nidorino was on board with adopting Totodile, especially knowing how much it meant to Nidorina, seeing as the two had shared a similar unfortunate childhood (though Totodile retained his innocence, being much younger). Of course, Eevee would return along with his real parents, turning Nidorino from foster dad to foster uncle, and having a few kids around meant that he'd have to step up his game at the office, which we finally see in this series.
What Nidorino does or who he works for is never specified, but it is clearly some sort of bean counting office job, and we find out that though his supervisor, a Machamp, really likes him as an individual, he never seems to get any credit for his contributions, which causes Nidorino to feel like he has to work just that much harder to get that promotion he wants. Additionally, we learn that Nidorina contacts him while at work, at this time only by phone, to both provide moral support and to combat her loneliness, her love for Nidorino growing stronger every episode.
The birth of their second child, Diana, triggers something in both Nidorina and Nidorino. For Nidorina, it increased her maximum capacity for happiness and love, and gave her a sense of self awareness that Nidorino must truly love her a lot to go this far with her. In turn, it vastly increased the amount of romantic feelings Nidorina held for Nidorino, as well as her self confidence as an attractive woman. Nidorino, however, became panicked by the fact that another child would mean a harder struggle, and that now getting that promotion was a must!
Nidorino began to work more hours and extra shifts, agreed to become a personal assistant and took on extra work to do at home. The timing for this couldn't be any worse as Nidorina became a lot more flirty with Nidorino. She realized she was desirable, but she also couldn't help the deep, irrational but wonderful, genuine feelings of love and passion that she had for Nidorino. Nidorino always had work to do, though, and he would always try to use this as an excuse (failing almost every time). Feeling a bit like his family was keeping him from getting ahead, he became distant again. This time, however, it was out of misguided good intentions. Nidorina noticed his erratic behavior, but ignored it and pretended as if everything was normal. She would continue to tease Nidorino, hoping to draw him away from his work and spend some time with her, but it just pushed him away further, now opting to just stay at the office for extended periods of time as opposed to bringing work home. Nidorina, braver and wiser, confronted Nidorino about this, but Nidorino's pride kept him from opening up, and admitting his fear that he might not be enough for them.
Some time later, Nidorino would finally open up to Butterfree about his feelings, and Butterfree helps him get past his personal anxiety and feeling of inadequacy. Butterfree is able to get it into Nidorino's head that he's lucky to have a family who loves him unconditionally, and nothing will ever change that. Nidorino finally tells Nidorina everything, and about his talks with Butterfree. With that weight off his shoulders, and knowing Nidorina would always be his partner and best friend, he began to spend more time with the wife and kids.
The final test of strength for Nidorino's marriage would be the premature birth of their daughter, Nina. Nidorina had never been so shaken since Poke Tales, and Nidorino knew he had to be her solid rock to keep her from a complete, and likely irreversible emotional breakdown, even if he himself felt like he was wondering in darkness. The entirety of this event coupled with the relief of Nina being okay solidified their marriage as a strong one that could last through anything, and my oh my, after this ordeal, you'd never seen a couple so happy to be together. The two sweethearts became very flirty and giggly, lots of hand holding, winking, butt pats and making out in public with little provocation. It was as though they finally got the honeymoon that they never had a chance to have in Poke Tales, and they remained this way until the series end.
By the series finale, Nidorino gets that promotion he's been after so for so long, but actually chooses to work far less so he can spend more time with the family that he adores, and his wife and best friend Nidorina, the one who stayed by his side for so long, and never stopped loving him with all her heart.
Personality, Quirks and Other Tidbits
The modern depiction of Nidorino combines his more shy, apologetic and confrontation avoiding personality after Diana's birth with his end of series, confident, self assured and loving personality. It's an interesting blend as it allows Nidorino to assume the role of a very caring father and loving husband without being too mushy-gushy with his wife, allowing her to continue to make passes at him just like the middle of the Poke Legends series. It also allows him to try to deter Nidorina's overeagerness as just a matter of tact rather than avoidance for work related reasons. At any given time he can start flirting with Nidorina, but it seems more fun to keep the mid series gag going, although now far more benign.
Well, what else is there to know?
- Nidorino is very reasonable and down-to-earth, within his family and outside of it. He may over analyze things or focus a little to hard on the minutiae, but he means well. He tends to be a foil to Nidorina's antics, keeping her feet planted on the ground, something that he had to do ever since they started dating, but he doesn't mind this. In fact, he really thinks he has a very positive impact on her, and while she would agree this is true, she does wish he'd stop nagging her over what she feels are trivial matters.
- Nidorino's personality and design was conceptualized for the same reason Nidorina's was: to provide a cute alternative who went against the gnarly-faced, hotheaded perception, and also had real feelings too.
- Nidorino is very much a straight man in terms of characterization, and gets dragged along for the ride far more than being one who makes a scene, save for a few times in the series. Nidorino Eto, Nidorino's successor, also started off this way before developing into someone far less responsible or grounded.
- Nidorino is somewhat eclectic, in so far as he'll do whatever the family wants to do. However, he doesn't have any strong preferences.
- He's one of the few major characters of any series to have no interest in gaming, at least beyond a quarter here or there spent on a pinball machine or Donkey Kong, your typical older generation go tos.
- It is known that Nidorino was considered very popular in high school, not only for his looks, but for his general amiability and being the school's good guy without being the goody two-shoes.
- Though Nidorino would prefer to avoid all confrontation, the claws (or perhaps the horn) have come out on occasion, typically when under attack. During the devastation arc in Poke Legends, both Nidorina and Nidorino went into a combative mode to do their best not only to protect their family, but all of their friends, too.
- Nidorino is actually far more attracted to Nidorina than he lets on, and he only drops the charade in canon after the birth of Nina, finally approaching Nidorina on her own level. In non-canon works, however, he does his best to keep his composure. Either way, it's actually hard for him to do, and Nidorina doesn't help.
- Even in series, Nidorino has moments of dropping his composure and drooling over Nidorina like a wolf over Red in a Tex Avery cartoon (prior to Nina). This is usually a gag, though, and doesn't last very long (about as long as Droopy bounces around out of character, on the subject of a Tex Avery cartoon). Other times, a different sort of gag is played where Nidorino shows interest and Nidorina is uncharacteristically nonchalant or preoccupied. Mutual moments have and still do happen, though.
- Even when he's staying cool, Nidorino actually loves the attention he gets from Nidorina. There are moments where even he can't help but brag about how great the chemistry he and his wife have, as friends, parents and lovers as well.
- Nidorino is a bit jealous of Nidorina in that his only biological son, Needles, has a preference for her instead of him. This type of jealousy is mostly playful and also understanding, however.
- Nidorino considers Nidorina his best friend, and they talk to each other about anything and everything. Usually during walks or non specific outings, they carry on long conversations, laughing and joking and gasping and playfully shoving. They also openly talk about things that bother them, though in Nidorino's case he hasn't always been upfront.
- Nidorino loves Nidorina deeply, and though he doesn't show it in outward affection so much, would never do anything to hurt her. In fact, seeing Nidorina sad or in pain fills his own heart with a deep sadness, and he will typically stay by Nidorina's side as long as she needs him, no matter what else is going on (save for another family emergency). This, of course, is assuming we mean Nidorino after the remarriage and not distant-indifferent Nidorino from the first half of Poke Tales.